now I installed streams. What is the next step. 
Good news I have the login page. 
Do I have to use the email of yunohost admin to be admin ?

Is it possible to change it later ? 

I am a bit confused 

 @37bb158f I don't remember off the top of my head. I think you create a new user, and the first user is admin. 
I could be wrong. But I think that's how it works